After screen replacement camera's did not work anymore

I had a Iphone 5S of which the front glas / digitizer broke. At that time both camera's were working.

I had a full front original LCD with digitizer with earpiece and front camera preinstalled. I turned off the phone, replaced the screen, but when I opened the camera app, the iphone 5s rebooted.

Then I decided to remove the earpiece and front camera from the broken screen, and put those parts on the new sceeen. At that time the camera app did crash, it just closed and went back to the menu.

I decided to upgrade IOS 7.0.4 -> 8.0.2 but at that time both camera's showed a black screen at the camera app. No sound could be heart of a shutter which opened, just nothing. Completely erased the phone, no difference.

When I replaced everything, I was discharged from static energie also used a plastic spudger to disconnect the connectors.

Actually I did everything very carefully and really don't know what happened.

Do you have a clue of what could have happened ?

I remember another time that I enabled console logging in Iphone configuration Utility, but console logging does not show anything anymore. Does anyone know how to enable console logging on this IOS ?